Phase-accurate generation of quantum-computing control signals

A method for generating at least two signals Sk with k=1 . . . K by a signal generator, wherein the signal generator comprises at least a first channel k′ and a second channel k″, with each channel k having

• a digital section adapted to generate a digital signal set comprising at least one digital signal having a frequency ωNCOk, wherein the digital signal set encodes digital phase information indicative of a phase shift φk,
• at least one digital-analog converter adapted to convert the digital signal set into an analog signal set comprising at least one analog signal having a frequency ωNCOk wherein the analog signal set encodes the information indicative of the phase shift φk,
• an up-converter comprising a local oscillator adapted to generate an analog oscillator signal at a frequency ωLOk and a mixer adapted to generate an up-converted signal from the analog oscillator signal and the analog signal set, wherein the up-converted signal has a frequency of ωLOk±ωNCOk with the phase shift φk,
• said method comprising:
• generating, at a time t0, a first pulse with the first channel k′ and a first pulse with the second channel k″,
• generating, at a time ti, a second pulse with the first channel k′ and a second pulse with the second channel k″,
• operating, during both times t0 and t1,
• the local oscillator of the first channel k′ at a frequency ωLOk′,
• the local oscillator of the second channel k″ at a frequency ωLOk″,
• the numerically controlled oscillator of the first channel at a frequency ωNCOk′,
• the numerically controlled oscillator of the second channel at a frequency ωNCOk″;
• operating the digital sections of both channels at the times t0 and t1 to generate pulse envelopes for the pulses,
• changing, between the times t0 and t1, at least one of
• the phase shift φk′ of the first channel and
• the phase shift ωk″ of the second channel,
• while maintaining
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• with φk′0 and φk′1 being the phase shifts of the first channel at the times t0 and t1, respectively and φk″0 and φk″1 being the phase shifts of the second channel at the times t0 and t1, respectively.